Polyethylene Injection Molding Service

Custom Polyethylene Injection Molding Service

NOBLE specializes in providing tailored precision injection molding services for polyethylene, ranging from rapid prototyping to large-scale production. This comprehensive approach ensures that you can receive high-quality polyethylene parts or prototypes in just a few days. Request your custom injection molded polyethylene components online today, with delivery available in as little as 3 days.

Our Polyethylene Injection Molding Capabilities

NOBLE offers personalized injection molding services tailored to each customer’s unique needs, from prototype design to full-scale production. We deliver high-precision, high-performance polyethylene parts at competitive prices. Our advanced manufacturing capabilities enable us to produce industrial-quality polyethylene components with tight tolerances, as precise as +/- 0.001 inches.

Price	$$$
Lead Time	< 5 days
Wall Thickness	0.047 in. – 0.140 in
Tolerances	+/- 0.003 in. (0.08mm) with an included polyethylene tolerance that can be greater than but no less than +/- 0.002 in./in. (0.002mm/mm)
Max Part Size	20 in. x 29.3 in. x 8.2 in
Available Polyethylene at NOBLE	LDPE, HDPE, UHMW-PE, PEX, MDPE

Characteristics of Polyethylene Injection Molding Materials

At NOBLE, we leverage our robust manufacturing capabilities at our domestic factories in China to offer high-quality injection molding solutions, with a wide range of surface finish options and versatile material choices.

Features	Info
Subtypes	LDPE, HDPE, UHMW-PE, PEX, MDPE
Process	Injection molding, CNC machining
Tolerance	+/- 0.003 in. (0.08mm) with an included polyethylene tolerance that can be greater than but no less than +/- 0.002 in./in. (0.002mm/mm)
Applications	Medical Devices, Automotive Parts, Automation Industry, New Energy, Industrial Components, Consumer Goods
Finishing Options	Polishing, Heat Transfer Printing, Sand Blasting, Powder Coating, Flame Polishing

Pros and Cons of Polyethylene for Injection Molding

Polyethylene offers key advantages in Injection molding, including ease of processing, high precision, and cost-effectiveness, especially for prototyping. However, challenges such as brittleness, limited heat resistance, and chemical sensitivity must also be taken into account. We will select the best material for your needs and customize a Injection molding production plan to give you a competitive edge!

Ease of Molding

Polyethylene is easy to mold due to its low viscosity and good flow properties, making it ideal for producing complex shapes with minimal scrap. It is well-suited for prototypes, small batches, and custom designs.

Low Tool Wear

Polyethylene causes minimal wear on injection molding tooling due to its relatively low hardness and smooth flow characteristics. This extends tool life, reduces maintenance costs, and supports long production runs with fewer tool replacements.

Lightweight

Polyethylene is a low-density material, making it lightweight and easy to handle during the injection molding process. Its reduced weight also lessens the load on injection molding machines, improving processing efficiency and reducing energy consumption.

Low Cost

Polyethylene is an affordable material compared to metals and other engineering plastics. Its low cost and ease of injection molding make it ideal for budget-conscious projects, providing excellent performance in cost-sensitive applications without sacrificing quality.

Versatility in Applications

Polyethylene’s various grades, including LDPE, HDPE, and UHMW-PE, offer flexibility to meet different mechanical, thermal, and chemical requirements. This versatility, combined with its ease of injection molding, makes it suitable for a wide range of applications, from industrial components to consumer products.

Low Thermal Resistance

Polyethylene has a relatively low heat deflection temperature, which can cause softening or warping during high-temperature injection molding. This limits its use in high-temperature applications and requires careful temperature control during the molding process to avoid dimensional instability or surface deformation.

Susceptibility to Creep

Polyethylene can experience creep (slow deformation under stress), particularly at higher temperatures or in continuous load conditions. This limits its use in high-load, high-temperature applications and requires careful material selection and design to ensure long-term stability in injection molded parts.

Poor UV Resistance

Polyethylene degrades when exposed to UV light, resulting in surface cracking and loss of mechanical properties. This limits its outdoor use unless treated with UV inhibitors or coatings, which would require additional steps during the injection molding process for surface treatment.

Limited High-Temperature Performance

Polyethylene’s relatively low melting point limits its use in applications involving high temperatures. Injection molding at high temperatures can cause material softening, so careful control of molding conditions is essential to prevent deformation.

Difficult to Bond or Paint

Polyethylene’s low surface energy makes it challenging to bond or paint without surface treatment. Processes such as plasma or flame treatment are required for proper adhesion, adding complexity and cost to applications that require coatings or bonding.

Environmental Concerns

Although recyclable, polyethylene is not biodegradable, raising concerns about waste and environmental impact, particularly in single-use or large-scale applications. Recycling programs and alternative materials can help mitigate these concerns.

Types of Polyethylene Injection Molding Materials

Polyethylene (PE) is one of the most widely used plastics, known for its versatility, ease of injection molding, and affordability. It is available in several grades, each with distinct physical and chemical properties tailored to specific applications.

Low-Density Polyethylene (LDPE)

LDPE is a flexible, transparent, and lightweight material with relatively low tensile strength. This makes it ideal for applications like plastic bags, films, and tubing. Injection molding of LDPE requires slower injection speeds and careful temperature control to prevent deformation. Effective cooling is crucial to prevent material softening and excessive tool wear.

Tensile Modulus: 150–500 MPa

Tensile Strain (Yield): 100–600% (depending on grade)

Rockwell Hardness: 30–45 R

Heat Deflection Temperature: 120–130°F

High-Density Polyethylene (HDPE)

HDPE is a strong, rigid material known for its high impact resistance. It is commonly used for applications like bottles, pipes, and cutting boards. Injection molding of HDPE requires higher injection pressures and careful control of cooling rates to avoid warping and ensure clean, precise parts. The use of sharp molds helps achieve better detail and smoother surfaces.

Tensile Modulus: 800–1,200 MPa

Tensile Strain (Yield): 5–10%

Rockwell Hardness: 65–75 R

Heat Deflection Temperature: 130–160°F (54–71°C)

Ultra-High Molecular Weight Polyethylene (UHMW-PE)

UHMW-PE excels in wear resistance, low friction, and impact strength, making it ideal for demanding industrial applications such as conveyor systems and medical devices. Injection molding of UHMW-PE requires slower injection speeds, specialized molds, and careful temperature management to minimize tool wear and achieve a smooth surface finish.

Tensile Modulus: 1,000–1,500 MPa

Tensile Strain (Yield): 100–300% (depending on formulation)

Rockwell Hardness: 65–80 R

Heat Deflection Temperature: 180–190°F

Cross-Linked Polyethylene (PEX)

PEX, known for its enhanced heat and chemical resistance, is commonly used in plumbing systems and underfloor heating applications. Injection molding of PEX requires precise temperature and pressure control due to its tough, cross-linked structure. Cooling systems are essential to prevent overheating and cracking during the injection molding process, ensuring dimensional stability and high-quality surface finishes.

Tensile Modulus: 300–500 MPa

Tensile Strain (Yield): 30–60%

Rockwell Hardness: 50–65 R

Heat Deflection Temperature: 180–220°F

Medium-Density Polyethylene (MDPE)

MDPE strikes a balance between flexibility and strength, making it ideal for applications such as gas pipes and packaging films. Injection molding of MDPE requires moderate injection speeds, precise control of cooling, and sharp tooling to prevent deformation. The material’s balance of properties makes it suitable for both durable and flexible components.

Tensile Modulus: 400–800 MPa

Tensile Strain (Yield): 50–300%

Rockwell Hardness: 55–70 R

Heat Deflection Temperature: 150–170°F

Surface Finishing Options for Polyethylene Injection Molding

When injection molding polyethylene, surface finishing is often required to improve its appearance, performance, and durability across various applications. NOBLE offers a range of tailored surface treatments to enhance both the mechanical properties and aesthetics of each molded part, ensuring optimal quality and performance.

Polishing

Working on metal and hard plastics, our polishing uses highly efficient machinery to get our parts between Ra 0.8~Ra0.1 for a cleaner surface.

Heat Transfer Printing

Heat Transfer Printing applies heat and pressure to transfer designs onto surfaces, creating durable, vibrant graphics suitable for various materials.

Sand Blasting

Sand blasting cleans the surface of any impurities and peels coating through the propelling of blast media streams over the parts.

Powder coating

We apply a thin layer of protective polymer with the corona discharge phenomenon to give our part a lasting finish that protects from impacts and prevents wearing down.

Flame Polishing

Flame polishing uses a controlled flame to slightly melt the surface of polyethylene, smoothing out imperfections and creating a high-gloss finish. It’s commonly used for clear polyethylene parts where aesthetics are crucial.

Custom Polyethylene Injection Molding Parts Display

Check out our over a decade of custom polyethylene injection molding, including precision polyethylene prototypes and parts from our valued customers.

Applications of Polyethylene Injection Molding

Polyethylene (PE) is one of the most widely used materials in injection molding, known for its versatility, ease of processing, and a range of beneficial properties. NOBLE offers comprehensive custom polyethylene manufacturing, from prototyping to full-scale production. We provide high-quality polyethylene parts that meet industry standards, with fast turnaround times, expert guidance, and a commitment to uncompromising quality.

If you are looking for a rapid prototyping manufacturer or a CNC machine shop to fabricate small, medium-volume, or mass-production products, NOBLE is an ideal choice.Our well-trained and experienced staff manufactures parts in line with drawings on modern CNC machines, with the highest accuracy and processing quality in all sizes.In addition, we provide professional design considerations for your CNC machining projects.

Want to get the most professional and fastest service for your CNC machining project? Upload your CAD files now and obtain a quote!